Cardiac surgery for the adolescent with univentricular heart.

Univentricular heart is a complex congenital anomaly with an extremely dismal prognosis. Left untreated the majority of patients will die in infancy. This poor outlook has prompted an aggressive surgical approach consisting of early palliation followed by eventual complete repair. The initial palliative efforts are aimed at providing adequate arterial oxygen saturation and normalizing pulmonary artery pressure. Infants with severe cyanosis due to diminished pulmonary blood flow are best treated with a systemic to pulmonary artery shunt. Those with excessive pulmonary flow and hypertension must be banded early to prevent pulmonary vascular occlusive disease. Most patients who are properly palliated will become acceptable candidates for an eventual corrective procedure. For the majority, this will be a direct atriopulmonary connection, known as the Fontan procedure. In this operation, systemic venous blood is routed directly to the pulmonary artery, excluding the ventricular mass. Although not corrective in the usual sense, this procedure provides normal arterial saturation without ventricular volume overload. A small group of patients with univentricular heart may best be treated by partitioning the ventricular chamber into 2 halves. Septation procedures, however, carry a high operative mortality and are likely to result in complete heart block. These surgical options, when properly selected and timed, have improved the outlook for many children with univentricular heart.